login
A193499
Number of n X n symmetric 0..2 arrays with no element equal to the product mod 3 of any two of its horizontal and vertical neighbors
1
3, 11, 62, 508, 6113, 111924, 3135173, 135866492, 9010404513, 922993092986, 145088171122406, 35156227235312406, 13079571591787830274, 7493880039061547385152, 6595187964080142141837198
OFFSET
1,1
LINKS
EXAMPLE
Some solutions for 4X4
..1..0..2..0....2..2..2..0....2..2..0..2....2..2..2..2....0..2..2..0
..0..2..2..2....2..2..0..2....2..2..2..0....2..2..0..2....2..2..0..1
..2..2..0..2....2..0..1..0....0..2..0..1....2..0..1..0....2..0..1..0
..0..2..2..2....0..2..0..2....2..0..1..2....2..2..0..2....0..1..0..1
CROSSREFS
Sequence in context: A356268 A069725 A291287 * A261919 A232617 A326092
KEYWORD
nonn
AUTHOR
R. H. Hardin Jul 29 2011
STATUS
approved